二次风对骨料烘干煤粉燃烧器的影响分析

Analysis of secondary air impacting on pulverized coal burner of aggregate drying

合理的参数选择是提高煤粉燃烧效率的关键。针对特定的煤粉燃烧器内部动力场,建立合理的数学模型,对其进行数值仿真,分析二次风的风速及旋流强度对温度场、燃烧率、平均混合物分数、CO质量分数的影响,其结果与燃烧理论有较好的一致性。进而得出二次风速度的合理取值范围为50m/s^60m/s,二次风旋流强度的合理取值范围为0.25~0.75,为煤粉燃烧的有效控制提供了理论基础。

Reasonable parameters selection is the key to improve the burning efficiency of pulverized coal .The paper firstly establishes a mathematic model for a certain burner .Then a series of numerical simulations are taken .The simulations show that the temperature field ,burning rate ,mean mixture fraction ,CO mass fractionare correspondingly effected by the secondary air speed and its swirl strength .The simulating results match the burning theory quite well .Finally ,the reasonable parameters can be acquired .Concretely ,the speed of the secondary airtakes from 50m/s to 60m/s and the swirl strength takes from 0 .25 to 0 .75 .Thus a theoretical basis can be provided to effectively control the pulverized coal burning .